Security equipment for audio apparatus

ABSTRACT

The invention relates to an equipment for preventing an audio apparatus being locked, when it becomes impossible to read in TOC information because of a fault or faults in a disk or an equipment for reproducing the disk. A security equipment for audio apparatus which releases a security operation based on a result of a comparison between a read in TOC information and a previously stored TOC information, the security equipment stopping a judgement on the TOC information when a failure is detected in the disk or the equipment for reproducing the disk (R1-4) at the time of reading in the TOC information. Thereby, the audio apparatus is not locked when the TOC information is read in, because the TOC information which was read in (R5) without a mechanical error, is correct.

TECHNICAL FIELD

The present invention relates to security equipment for an audioapparatus, particularly for protecting an audio apparatus for a vehiclefrom theft.

BACKGROUND ART

Various equipments for protecting an audio apparatus for a vehicle fromtheft have been proposed since such apparatuses are often stolen.

Among the various equipments proposed are security equipment for which auser can easily release a security operation even while the audioapparatus is executing the security operation without decreasingsecurity performance. A security equipment making use of TOC (TABLE OFCONTENTS) information of a compact disc (hereinafter referred to as"CD") and the like is proposed in Japanese patent application PH5-327672(Published Unexamined Patent Application (Kokai) PH7-182840).

The security equipment making use of the TOC information is explainedbelow.

The TOC information is information recorded on a read in area of a CDand the like. As shown in FIG. 5, the CD comprises a read in area 31, adata area 32, a read out area 33. The TOC information is recorded on aread in area 31, and it contains characteristic data (the number ofmusic tracks, the start of music data, and the playing time) of thedisk.

In order to set the security mode of the audio apparatus, TOCinformation of the prescribed CD is previously written into a memory ofthe audio apparatus, for example, an electrically erasable programmableROM (EEPROM) and the like.

If the audio apparatus is stolen from the vehicle under the conditionthat the security mode is set, the security operation is executed asfollows. When the audio apparatus is stolen from the vehicle, the audioapparatus is disconnected from the vehicle battery. The securityequipment detects this change of connecting condition with the batteryby a change of power source and stores it. When the audio apparatus isfitted to another vehicle and connected again to a battery, the securityequipment executes the security operation because the fact that thebattery has been once disconnected is stored. If the security operationis executed, the audio apparatus becomes inoperable and does not acceptswitching operation, etc. except when a special operation is executed.

Therefore, if a person other than the user takes the audio apparatusaway from the vehicle, the person cannot use the apparatus. Bydisplaying on the vehicle or on the apparatus that such a securityfunction is provided, it reduces the likelihood of theft.

However, if the security mode is set, it may occur that the audioapparatus becomes inoperable even while a user uses the audio apparatusproperly, because the security operation may be triggered by thedischarge of the vehicle battery and the like.

In order to reset the inoperable condition, the user inserts the CD usedfor setting up the security mode or an identical CD into the CD playerof the audio apparatus. The security equipment reads in the TOCinformation from the inserted CD, and if it is identical to the TOCinformation recorded in the memory, the security equipment resets theinoperable condition and the audio apparatus can be used as usual.

On the other hand, even though a person who stole the audio apparatusconnects the audio apparatus to a battery and tries to operate it, itcannot be used since it is in an inoperable condition as describedabove. For example, even if a CD is inserted into the CD player, thechance that the inserted CD is identical to the CD which was used to setup the security mode is very small. Thus if any other CD is inserted,the TOC information of the inserted CD is not identical with the TOCinformation in the memory. Therefore, the release of the securityoperation is not executed and the audio apparatus is kept inoperable.

When the insertion of a CD, which is not the prescribed CD, is repeatedmore than a defined number of times (i.e., five times or ten times), theinoperable condition cannot be released, and thus raises the reliabilityof the security.

If the user forgets or loses the CD which was used for setting thesecurity mode, the security mode can be released according to the properprocess of carrying it in to a dealer or the like.

SUMMARY OF THE INVENTION

In the conventional security equipment described above, when thesecurity operation is executed and the audio apparatus is in aninoperable condition, a user inserts the prescribed CD and releases theinoperable condition. The security equipment reads in the TOCinformation of the CD. However, there may occur cases where the securityequipment cannot read in the TOC information because there is a fault inthe disk or the reproduction apparatus for the disk.

In this case, according to the conventional security equipment, itcontinues the operation for reading in the TOC information until the TOCinformation can be read in. Therefore, the audio apparatus is lockedunder the above condition, and cannot enter the next operation. A useris able to recognize, for the first time, that the equipment has failedwhen this condition continues for a long time. In order to release theabove condition, the operation for reconnecting the electric power, etc.should be made.

When there is a fault in the disk or the apparatus for reproducing thedisk, even if the TOC information can be read in, there is a possibilityof an erroneous judgement because the TOC information is erroneouslyread in.

Therefore, the purpose of the invention is to prevent the audioequipment from being locked when the TOC information cannot be read in,because, in the security equipment for the audio apparatus using the TOCinformation, the operation for reading in the TOC information becomesimpossible because of faults in the disk or the reproduction apparatusfor the disk.

Further, the purpose of the invention is to increase the reliability ofsecurity in the security equipment for the audio apparatus using the TOCinformation, by not judging based on the erroneous TOC information, whenthere are faults in the disk or the apparatus for reproducing the disk.

To accomplish the above purposes, the present invention comprises, inthe security equipment for the audio apparatus which releases thesecurity operation based on the result of the comparison between theread in TOC information and the previously stored TOC information, ameans which detects a failure in the disk or the equipment forreproducing the disk when the TOC information is read in, and a meansfor stopping the judgement concerning the TOC information.

Thereby, when the audio apparatus mechanism fails, the reading in of theTOC information is stopped. Therefore, the audio apparatus is not lockedunder the condition of reading in the TOC information. The user may theneasily enter the operation for correcting the failure.

According to the invention, in addition to the above, the securityequipment may comprise a means to execute the judgement on the TOCinformation when the reading in means reads in the TOC informationwithout detecting a failure. The TOC information, which is read in whenthe disk or the apparatus for reproducing the disk has failed, may beincorrect. However, if the judgement is made based oil the correct TOCinformation which is read in when a failure is not detected thejudgement with respect to the release and the continuation of thesecurity operation will be executed correctly.

According to the invention, the security equipment may comprise a meanswhich detects a condition where there is no disk in the predeterminedplace (e.g. the first tray of a CD autochanger) when the TOC informationis read in, a means which stops the judgement on the TOC informationwhen the above detecting means detects the no disk condition. Thereby,the security operation may not be released when the inoperable conditionis not reset by the regular process by a user. Thus the invention mayincrease the reliability of the security.

Further, according to the invention, when the said detecting meansdetects a failure or the prescribed condition, it may demand that theuser inserts the prescribed disc by displaying that the disk or theapparatus for reproducing the disk has a fault or faults. Thereby, theuser may return the apparatus to the normal condition promptly byreinserting the disk.

As described above, according to the invention, in the securityequipment for the audio apparatus using the TOC information, it can beprevented that the audio apparatus becomes locked when the TOCinformation cannot be read in because there is a failure in the disk orthe apparatus for reading the disk.

In the security equipment for the audio apparatus, where the disc or theapparatus for reading the disc has failed, the reading in of the TOC isstopped. Therefore, since the judgement is not made based on theerroneous TOC information, the reliability of the security can beincreased.

When the condition without a disk in the prescribed place is detected,the judgement on the TOC information is stopped. Therefore, when theinoperable condition is not released by the regular process, the releaseof the security is not made, and thereby the reliability of the securityis increased.

Further, since a request for a change of the disk is displayed for theuser when a failure is detected, the user may change the disk promptlyin response to the display.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a flow chart (part 1) explaining the operation of anembodiment of the equipment according to the present invention.

FIG. 2 is a flow chart (part 2) explaining the operation of anembodiment of the equipment according to the present invention.

FIG. 3 is a block diagram of an embodiment of the audio apparatusaccording to the present invention.

FIG. 4 is a flow chart (part 3) explaining the operation of anembodiment of the equipment according to the present invention.

FIG. 5 is a record format of a CD.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, embodiments of the present invention will be explained byreferring to the accompanying drawings.

FIG. 3 illustrates a block diagram of an audio apparatus. The audioapparatus shown in FIG. 3 comprises a CD player, and the TOC informationis read in from the CD. However, the present invention may be applied toa digital audio disk player, a digital audio tape player, etc. otherthan the CD player in which the TOC information is recorded.

The illustrated audio apparatus comprises a CD player 2 which reads theinformation in the CD 1, reproduces an audio signal and reads out theread in information, a radio receiver 8 which receives a radiobroadcasting, an amplifier 5 which amplifies an audio signal from the CDplayer 2 and the radio receiver 8 and outputs a signal to a speaker 7,the microprocessor 4 which controls the CD player 2, the radio receiver8, the amplifier 5 and the security related operation, an EEPROM 3 whichstores the information for releasing the security operation, and theindicator 11.

A microprocessor 4 is connected through the ignition switch IGSW ordirectly to batteries B, and is always monitoring the connectingcondition with the batteries B. ROM 10, in which programs, etc. arestored, is included in the microprocessor 4.

FIG. 4 illustrates a flowchart which shows a main routine of the processperformed by the microprocessor 4. The process shown in the drawingstarts when the audio apparatus becomes operable by the operation of theignition key IGSW or an on-operation of the power source switch of theaudio apparatus.

At the step M1, it is judged whether the security mode is set or not. Itis judged that the security mode is set, if the TOC information iswritten in the EEPROM 3, and it is judged that the security mode is notset, if the TOC information is not written.

If the security mode is not set (N of the step M1), the audio apparatusis available as usual without setting the security mode. In thiscondition, it is possible to set the security mode. This setting isperformed, by the user, by means of selecting the specified compact disc(ID disc) and storing the contents (TOC data) recorded in the read-inarea 31 (FIG. 5) into the memory EEPROM 3 of the audio apparatus shownin FIG. 3.

If, at step M1, the security mode is set, it is judged whether theconnection between the audio apparatus and the batteries has beendisconnected or not. The microprocessor 4 always monitors the voltage ofthe connecting terminal with the batteries B, and, when a voltage drophas been detected, the microprocessor stores data indicating that avoltage drop has occurred. If it is detected, in step M2, it is judgedthat the batteries were disconnected.

If the batteries were not disconnected (N of step M2), the audioapparatus becomes available under the security mode as being set. Inthis condition, it is also possible to proceed to the process forreleasing the security mode. The security mode can be released byerasing the TOC data stored in the EEPROM of FIG. 3 (goes to the initialcondition).

If it is judged that the disconnection with the batteries occurred atstep M2, the security equipment performs the security operation and theaudio apparatus is in the inoperable condition. Next, it is judged, atstep M3, if it is under "a master carrying in mode", that is, it isjudged whether the inoperable condition should be released using themaster disc, etc. or not. If it is judged at step M3 that it is notunder "a master carrying in mode", the user performs the process forreleasing the inoperable condition. That is, releasing the inoperablecondition by inserting the prescribed CD (ID disc), and making the audioapparatus available as usual. If it is under "a master carrying in mode"at step M3, the user carries in the audio apparatus into a shop, etc.,and has to release the inoperable condition using the master disc, etc.

The process for releasing the inoperable condition will be explainedlater. "A master carrying in mode" is set when the process for releasingthe inoperable condition is improperly performed (e.g. a CD other thanthe prescribed CD is inserted a number of times exceeding the prescribednumber of times).

The process for releasing the inoperable condition is explained byreferring to FIG. 2. The process shown in FIG. 2 is the same asexplained in the above described Japanese Patent Application PH5-327672(Published Unexamined Patent Application (Kokai) PH7-182840) except thatthe step Q20 is inserted between step Q3 and step Q4.

When entering into the mode for releasing the inoperable condition, if adisk is in the CD player, the process for discharging it is performed atstep Q1. At step Q2, in order to prompt the insertion of the disk, thedisplay "DISK" is lit on the indicator 11, step Q3 and step Q2 arerepeated, and the player waits for the insertion of the disk. When thedisk is inserted, the control proceeds from the step Q3 to step Q20.

The contents of step Q20 will be described later. The TOC information isread in at step Q20. When the reading in starts, the display "DISK" onthe indicator is turned off.

At step Q4, a comparison between the read in TOC information and the TOCinformation recorded in the memory is performed, if they are coincident,the inoperable condition is released at step Q5 and the indicator 11displays that the inoperable condition is released, and the disk isdischarged at step Q6. Hereafter, the audio apparatus is available underthe condition that the security mode is set.

If the read in TOC information and the TOC information recorded in thememory are not coincident at step Q4, the control goes to the step Q7.After that, the process prompting the insertion of the normal CD isperformed, the control goes to the step Q5 from the step Q4 if thenormal CD is inserted. However, when a CD which is not normal isrepeatedly inserted, the control is proceeded to "the master input mode"process compulsorily or by a optional operation, "master input" isdisplayed on the indicator 11 at step Q15, then the disk is dischargedat step Q16.

The audio apparatus enters the master input mode under the conditionthat the inoperable condition is continued and the audio apparatusbecomes not available, if the inoperable condition is not releasedaccording to the normal way at a dealer, etc. The process after theabove step Q7 will be described below.

At step Q7, it is judged if both of the TOC data do not coincide fivetimes or ten times continuously, further it is also judged at step Q8 ifboth of the TOC data do not coincide ten times continuously. When bothof the TOC data do not coincide ten times continuously, the control goesto step Q15, then the display of a failure or a recommendation to go tothe dealer, etc. is made. After the compact disk is discharged at stepQ16, the control goes to the master input mode process.

When both of the TOC data do not coincide ten times continuously, thecontrol goes to the step Q11, the display for prompting thereconsideration as to if the inserted compact disk is the ID disk, ismade, and the compact disk is discharged at step Q12. At step Q13, it isjudged if the compulsory transfer operation to the master input mode isperformed. If it is performed, the control transfers to the step Q15. Ifit is not performed, it is judged, at step Q14, if one hour has passedsince the reconnecting of the CD player 2 with the batteries B. Theprocesses from step A11 to step Q13 are repeated, the control returns tothe step Q1 after one hour and continues the process. The compulsorytransfer operation to the master input mode is performed by theprescribed specific operation.

When the number that both of the TOC data do not coincide is other thana continuous five times or ten times, the control transfers to the stepQ9, the display of unreadable, or the display that the disk is differentfrom the ID disk and the number of times of the errors, is made. Thecompact disc is discharged at step Q10, and the control returns to thestep Q2, then continues the process.

Next, by referring to FIG. 1, the step Q20 of FIG. 2 will be explained.

The operation shown in FIG. 1 starts following the insertion of the diskat the step Q3 shown in FIG. 2. At steps R1-R4, errors in the disk orthe equipment for reproducing the disk are checked.

At step R1, it is judged if a magazine of the CD autochanger isinstalled. At the step R2, it is judged if there is a temperature error.The temperature sensor detects whether a temperature exceeds thetemperature at which the security equipment works normally, and it isjudged that there is a temperature error when it is exceeded.

At the step R3, it is judged if there is a focus error. At the step R4,it is judged if there is a mechanical error, such as the CD does notrotate or the changer does not work normally, etc.

If even one error is detected at the steps R1-R4, the control goes tothe step R7 without performing the read in of the TOC information, andthe display demanding a change of the disk is made by the indicator.When a failure is not detected at the steps R1-R4, the control goes tostep R5.

At the step R5, it is judged if the TOC information was read in from theinserted disk. When the TOC information is not read in, the controlreturns to the step R1.

When the TOC information was read in, it is checked that if the positionof the disk is at the first tray of the CD autochanger at step R6. Whenit is in the tray 1, the control goes to the step Q4 of FIG. 2, and, asexplained above, the read in TOC information is compared with the TOCinformation recorded in the memory. When the disk is not in the tray 1at the step R6, the control goes to the step R7.

At step R7, the indicator 11 displays "DISK" and turns it on and off, inorder to remind the user to change the disk, and the control returns tostep Q1 of FIG. 2. The user recognizes the turning on and off of theindication that the read in of the disk was not normally performed, andagain performs a process such as the insertion of the disk, etc.

With respect to the means for performing the steps R1-R6 explainedabove, the CD player 2 or the microprocessor 4 comprises the said means,and they are also used for other purposes.

According to the embodiment explained above, when the TOC information isnot read in because of the mechanical error, etc., the control may go tothe next process without being locked as it conventially occurred. Sincethe TOC information is not read in erroneously because the mechanicalerror was previously detected, the TOC information is correct when theTOC information is read in. Therefore, the TOC information is judgedcorrectly and the reliability of the security can be increased.

What is claimed is:
 1. A security equipment for audio apparatus which releases or continues a security operation based on a result of a judgement of a comparison between a read-in TABLE OF CONTENTS (TOC) information and a previously stored TOC information, the security equipment for the audio apparatus comprising:detecting means which detects a failure in a disk or an equipment for playing the disk when the TOC information is read in; stopping means which stops the judgement on the TOC information when the detecting means detect the failure.
 2. The security equipment for audio apparatus according to claim 1 further comprising:performing means which performs the judgement on the TABLE OF CONTENTS (TOC) information when the TOC information is read-in without detecting the failure by the detecting means.
 3. A security equipment for audio apparatus which releases or continues a security operation based on a result of a comparison between a read-in TABLE OF CONTENTS (TOC) information and a previously stored TOC information, the security equipment of the audio apparatus comprising:detecting means which detects a condition that no disk is in the prescribed place when the TOC information is read in; stopping means which stops the judgement on the TOC information when the detecting means detect the condition.
 4. The security equipment for audio apparatus according to claim 1 or 3 further comprising:display means which displays that there is a fault or faults in the disk or the equipment for playing the disk when the detecting means detects the failure or the condition. 